ATL HANNA: Extratropical - Discussion

[NEXRAD]

well KWT the European models agree with you and didn't think Hanna would pull NW so quickly.....more of a dive SW then a bend WNW to NW....

Which models and run-times? The 00Z Euro is in-line with the guidance envelope while the 00Z UKMET is a bit right of the 06Z GFDL.

- Jay

So I was referring to the UKMET and Euro models before yesterday. If you look back at the archive, the UKMET and Euro for several days agreed on this scenario. In fact both kept showing the East Coast of FL, especially South Florida as the target zone...

of course those two models have shifted in the past 1 or 2 runs to the dynamic model consensus...

Ah, yes. Thanks for the clarification.

Jay

[jlauderdal]

lets see if it survives with a center today, i think its 50/50 at best right now

[tolakram]

[NEXRAD]

lets see if it survives with a center today, i think its 50/50 at best right now

That is the biggest question for today's Hanna-monitoring. Even if the system retains a vigorous center, I still expect weakening given the satellite appearance. I'd not be surprised if the storm dropped to 45 or 50 knots later, barring that no surprise convective cluster can overcome the shear and situate directly over the storm center.

- Jay

[KWT]

It'll survive I suspect jlauderdal, whilst it is somewhat exposed ther eis still explosive convection not too far away.

Remember Chris survived as a totally naked swirl for a good few days and Hanna probably only needs to survive 24hrs before condtions improve somewhat...or at least forecasted to improve

edit- of course it will weaken but it should survive.

[Sanibel]

Yes, Blown Away. Those two 02/09/UTC trop points show a storm that is running up the back of the one ahead of it. I just can't see the track they are talking about happening in that case.

[gatorcane]

BTW --

I feel bad for Haiti, they appear to be a tropical cyclone magnet this year

Looks like more life-threatening and flooding rains are near.

[NEXRAD]

It'll survive I suspect jlauderdal, whilst it is somewhat exposed ther eis still explosive convection not too far away.

Remember Chris survived as a totally naked swirl for a good few days and Hanna probably only needs to survive 24hrs before condtions improve somewhat...or at least forecasted to improve

edit- of course it will weaken but it should survive.

It'll be very interesting to see whether the circulation presses further southwest or redevelopes nearer the deeper, sheared, convection. While not a forecast, I'd not be too surprised if Hanna's center is found somewhere between Great Inagua and far-east Cuba later today.

- Jay

[Wthrman13]

lets see if it survives with a center today, i think its 50/50 at best right now

It's highly likely the storm will survive. You can't just get rid of a ~990 mb low that quickly, even under the destructive shear it's experiencing right now.

While I think the models may be too quick to retrograde the UL trough to the N of Hanna, they are all still in excellent agreement that this will indeed be the case, shifting the shear axis west with time and building in a large UL anticyclone over the top of Hanna. We could see things turn around in a real hurry, it's just a matter of timing for when and where this happens, and how strong Hanna would be when it eventually makes landfall.

[gatorcane]

Hey Jay,

Looking at the first few visibles from this loop, looks like Hanna is moving noticeably SW this morning as the naked swirl is evident.

What do you think?

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

[NEXRAD]

Hey Jay,

Looking at the first few visibles from this loop, looks like Hanna is moving noticeably SW this morning as the naked swirl is evident.

What do you think?

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

Definitely a jump, based on the lower level clouds. If it keeps up for the next few hours, then I'd call it a movement.

For what it's worth, the RUC/2 Theta-E pattern suggests (to me) that Hanna will favor a short-range SW progression followed by a more west track later today. Of course, many people dismiss the RUC/2 entirely for tropical weather forecasting, and don't consider Theta-E much either, but using both helped me discern Charley's (2004) and Fay's movements.

- Jay

[Trader Ron]

Hey Jay,

Looking at the first few visibles from this loop, looks like Hanna is moving noticeably SW this morning as the naked swirl is evident.

What do you think?

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

We have gone from The Great Atlantic Hurricane ( JB's words) to a naked swirl in less than 24 hrs.

[KWT]

Wthrman13, indeed I agree once shear eases we could see a very sharp 180 turn, remember that Hanna still is producing some very deep convection even if it is displaced now from the LLC and if the shear eases off thenthe center should steadily develop that deep convection over its center again.

[Sanibel]

I feel bad for Haiti

Good point. They had convection parked over them yesterday. I think it was Jeanne that hardly looked like anything while it was over Haiti but killed many.

[caneseddy]

Wthrman13, indeed I agree once shear eases we could see a very sharp 180 turn, remember that Hanna still is producing some very deep convection even if it is displaced now from the LLC and if the shear eases off thenthe center should steadily develop that deep convection over its center again.

Knowing the history of this storm and how it has behaved, if it can shake off the shear currently, then it can ramp up. Look how it intensified the first time when it finally got rid of the ULL

[gtsmith]

Hey Jay,

Looking at the first few visibles from this loop, looks like Hanna is moving noticeably SW this morning as the naked swirl is evident.

What do you think?

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

We have gone from The Great Atlantic Hurricane ( JB's words) to a naked swirl in less than 24 hrs.

yeah...nuff said about JB...

[NEXRAD]

The 12Z NAM is just starting to come in, but it seems initialized a little too far south and east (by perhaps 20 to 25 miles). Otherwise, the visible imagery and microwave imagery show Hanna's low level circulation is at least well organized. I'd not write the system off just yet; there remains another 8 to 16 hours remaining before shear starts to lessen.

- Jay

[meteorologyman]

The 12Z NAM is just starting to come in, but it seems initialized a little too far south and east (by perhaps 20 to 25 miles). Otherwise, the visible imagery and microwave imagery show Hanna's low level circulation is at least well organized. I'd not write the system off just yet; there remains another 8 to 16 hours remaining before shear starts to lessen.

- Jay

8 to 16 hours of shear I figure it would be a little more than that well then I'll take the 16 hours over the 8.

[gatorcane]

Is that dark area pushing southward the "ridge" building southward that should start the NW or WNW movement of Hanna?

If so I'm having a hard time believing a NW or NNW movement.....especially because it seems that ridge is building westward towards the Carolinas in this loop

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

and look at this loop...

is that big ULL off Nova Scotia retrograding back West and what are the track implications of Hanna because of this?

http://metofis.rsmas.miami.edu/~dortt/s ... 1_loop.gif

[carversteve]

Just a question..how fast is ike moving and will it disrupt hanna in any way? Hanna does not look well! And models still predict a south carolina landfall with Hanna..How is that looking? And they still show a cat 2 at landfall and have heard it could be a low end cat 3..Just a few questions i have..Thank you in advance for any comments!!........The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products